The present disclosure relates generally to magnetic resonance imaging (MRI), and particularly to a magnet suitable for MR guided interventional procedures.
Magnetic resonance (MR) guided interventional procedures have the potential of providing significant benefit to a patient, such as where tumor resections leave behind tumor tissue that may be removed with MR guidance. Minimally invasive techniques, such as MR guidance and therapy monitoring for laser, RF (radio frequency) and cryo ablation, may benefit the patient by saving the patient from a more invasive surgery that has a longer associated recovery time. However, present cylindrical magnets and open magnets have restricted access for such MR guided interventional procedures. Full size double-donut magnet configurations may provide increased physician access, but they have been limited to 0.5 T (Tesla) with a limited SNR (signal to noise ratio) and limited applications. As medical advances are made, minimally invasive surgeons are looking for apparatus and techniques that allow them to image fiber bundles in the brain during surgery to avoid damage to these areas during the surgery. With present 0.5 T magnets, this application cannot be completed in a timely fashion. In addition, access between the magnet halves does not allow enough room for physician assistants. In other areas, MR guidance may be used for insertion of catheters for biopsy extraction or introduction of stents. In many of these applications, a relatively small field of view (FOV) is sufficient for the intervention if the patient can be moved to keep the patient's anatomy of interest within the homogeneous region.
Accordingly, there is a need in the art of MR guided interventional procedures for a MRI magnet that overcomes the aforementioned drawbacks and provides additional advantages.